I am no expert, but, seems to me that coins I have that have these kinds of issues would just get worse if I tried to get them off. Unless I am not seeing your images properly, these areas already have outer layers removed and in fact what the "rust" is is already gone. Unless there is a reason, I just leave this stuff as trying to take it off makes matters worse. I personally have never used wax, but maybe that would make it look better. I like coins as they are, though, to me wax is an unnatural manipulation that I don't want.
Virgil